So the point is that install base isn't everything. There are other factors to consider that could lead developers to put games on lower selling systems. D'oh, really?
Yet to support this point you used first week sales of two single-platform DS games with no good parallel on another system. And one of which (Inazuma 11), which with the same first week multiplier as Prof. Layton 1, would end up selling a respectable 300K copies.
It doesn't speak well that you can't come up with good evidence to support a point that is very nearly self-evident.
You could have just looked at all the Wii/360/PS3 multi-plats that have come out in America over the last several months, and how Wii has a major advantage with some, and 360 has an even bigger advantage with others, despite the similar install base.
"[Our former customers] are unable to find software which they WANT to play."
"The way to solve this problem lies in how to communicate what kind of games [they CAN play]."
Satoru Iwata, Nintendo President. Only slightly paraphrased.
